1. Field of the Invention
This invention relates to a power consumption display device which enables display of power consumption of each power consuming element of a machine and power consumption per cycle of manufacture of products.
2. Description of the Prior Art
In Japanese Patent Application Laid-open No. 7-32430, there is disclosed a controller usable as a power consumption display device for a machine. However, since this controller is merely effective in finding and displaying only power consumption or average power consumption of a screw rotating motor of an injection molding machine every molding cycle, and makes it impossible to monitor the power consumption state concerned with other motors, servo motors and band heaters or like power consuming elements or the overall power consumption state of the whole of the machine, it is difficult to derive information required for attainment of effective power utilization and information required for calculation of product cost.
It is an object of the present invention to provide a machine power consumption display device which may display effectively information required for attainment of effective power utilization information required for calculation of machined product cost and so on.
Particularly, the present invention aims at providing a device for finding and displaying power consumption per cycle of a machine, which is effective in manufacturing products or carrying out predetermined work by repeating the same operation cyclically.
To attain the above object, a power consumption display device according to the present invention is configured to permit power consumption of each power consuming element or the total sum of power consumption of power consuming elements to be displayed, printed, stored in, a storage medium or outputted to a communication line every machine operation process or every predetermined time period.
Display of power consumption of each power consuming element for every machine operation process makes the weight of power consumption between the power consuming elements clear to attain information required for effective power utilization. Further, the display of power consumption of each power consuming element or that of the total sum of power consumption for every predetermined time period makes the transition of power consumption in terms of time clear to easily ascertain the influence of machine operating conditions upon the power consumption of the power consuming elements or easily detect a period of time suitable for machine operation.
The predetermined time period can be units of hours, units of days or units of the time longer than a day.
Further, the power consumption display device is effective in displaying an integrated value of power consumption of the power consuming elements in a predetermined period of time or the total sum of integrated values of power consumption of the power consuming elements in a predetermined period of time.
The integrated value of power consumption or the total sum of integrated values of power consumption may be counted by the unit of hour, day or any time longer than a day.
Further, the integrated value of power consumption or the total sum of integrated values of power consumption may be displayed for every machine operation process.
The power consumption may be displayed by numeric or graphic representation or by both numeric and graphic representations. Further, display of power consumption in time series makes the transition of power consumption in terms of time for each power consuming element and that of overall power consumption of the power consuming elements more clear.
The power consumption is measured by a power measuring unit of each power consuming element or is calculated by detecting drive current of an amplifier for driving each power consuming element.
According to the present invention, since the power consumption display device may display the power consumption of each power consuming element concerned with drive or control of a machine for every predetermined time period, it is possible to easily recognize the presence or absence of abnormality of each individual power consuming element, the balance of overall power consumption concerned with the power consuming elements and so on. Further, in the case of making alterations on the machine operating conditions, it is possible to easily observe how the alterations exert an influence upon the power consumption of the power consuming elements.
In case of an electromotive injection molding machine, an electric discharge machine, a press machine, machine tools, an industrial robot or like machine which is effective in manufacturing the same products or carrying out the same work by repeating the same operation, since the transition of power consumption of the machine per cycle of repetitive operation or that of power consumption of each power consuming element is displayed in time series, it is possible to calculate power rates per machined product and also per cycle of repetitive operation. It is also possible to make the time-series transition of power consumption of each power consuming element or that of overall power consumption of the power consuming elements dear to thereby easily find a period of time suitable for machine operation.